Greinar (Vísindafélag Íslendinga) - 01.01.1977, Page 112

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by the Ewings, as 10 raillion years, is naturally meaningless,
but we see no reason for remarking on the basis of that dating,
We should finally add, that just as the uplifted crestal axial
zone of the Reykjanes Ridge corresponds to the uplifts form-
ing a mountain chain along the Reykjanes Peninsula, at least
as far as Þingvallavatn (the provisory end of the uplifted
chain being the Hengill mountain) due to a strong stress field
probably just before the beginning of the last Pleistocene gla-
ciation, we find in the earlier strong global stress fields at
early and late stages of the older Pleistocene glaciations, an
explanation of the whole system of the narrower axial parts
of submarine ridges.
It is not at all strange that the pre-Tertiary, in part con-
solidated sediments of the main ocean bottoms thicken and
strengthen the suboceanic crust from the median zone towards
the continents. Therefore, it would just be the median zone
which yielded most easily to the strong Pleistocene global stress
fields, and formed the ridge system in a mid-oceanic position.
Why the East Pacific Rise does only touch the North American
continent, is then also clear.